A locking device of this type has become known from German Patent DE-PS 10 39 368. The prior-art locking device is arranged on a container of a respirator, which container consists of two container shells, and the container shells are designed as groove-like, double-walled shells at their front surfaces for accommodating a sealing material connecting the container shells to one another. To stabilize the sealing area, edges, which project to the outside and are surrounded by a clamp-like strap with a lock, are provided at the front surfaces of each container shell. To open the container, the strap is removed from the edges by pulling the lock, and the sealing material is severed at the same time with a tear wire. The gas mask and breathing equipment can then be removed from the container.
One disadvantage of the prior-art locking device is the fact that the sealing material is destroyed during the opening of the container, which makes handling difficult in those cases in which the container must be opened only briefly for testing purposes. In addition, valuable time is lost in the case of use due to the fact that the strap must first be bent off from the edges and the tear wire must be pulled off all around the edges.
A locking device for a portable container, which consists of two shells and in which the shells are held together by straps arranged in a star-shaped pattern, has become known from DE-A 36,39,421. A uniform sealing pressure is exerted by the straps on a sealing ring, which is located between the front surfaces of the container and lies flatly on the front surfaces. The strap design is very complicated for achieving a uniform contact pressure on the sealing ring.
German Patent DE-PS 623 153 discloses a container with a cover for a breathing mask, which cover is pivotable around a hinge and uses a cover lock in such a way that the cover is raised during opening. Such a lock cannot be used for containers with long sealing areas, because the locking forces act only at two points, namely, that of the lock and that of the hinge, and in the other areas there is a risk that the container will leak due to lack of contact pressure on the seal.